Sand-blasting apparatus



(No Mariel) l 2 Sheets-Sheet 1. B. G. TILGHMAN, Jr.

SAND BLASTING APPARATUS. No. 584,021. Patented June 8,1897.

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B. C. TILGHMAN, Jr.

SAND BLASTING APPARATUS.

Patented June 8,1897.

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BENJAMIN C. TILGIIMAN, .IR., OF PHILADELPHIA, PENNSYLVANIA.

SAND-BLASTING APPARATUS.

SPEGIFIGATION forming part of Letters Patent No. 584,021, dated June 8, 1897.

Application filed January 8, 1897. Serial No. 618,446. (No model.)

To (all whom it may concern:

Be it known that i, BENJAMIN O. TILGH- MAN, Jr., a citizen of the United States of America, residing in Philadelphia, in the county of Philadelphia, in the State of Pennsylvania, have invented a certain new and useful Improvement in Sand-Blasting Apparatus, of which the following is a true and exact description, reference being had to the accompanying drawings, which form a part thereof.

My invention relates to apparatus to be used in connection with the sand-blast, and having for its object to collect and remove the dust, sand, &c., resulting from the operation of the sand-blast and the separation for reuse of such sand as is of proper weight and size for this purpose.

Particularly my invention is designed for such work as cleaning castings, though its usefulness is by no means limited to such employment.

The nature of myimprovements will be best understood as described in connection with the drawings, in which they are illustrated, and in which Figure 1 is a side elevation, partly in section, illustrating the apparatus as a whole and in the form in which I prefer to use it. Fig. 2 is a cross-sectional View taken as on the section-line 1 1 of Fig. 1, and Fig. 3 a vertical section taken as on the section-line 2 2 of Fig. 1.

A indicates the room or chamber in which is situated the sand-blasting apparatus and in which the article to be sand-blasted is introduced. This chamber should he substantially air-tight, but provided with one or more regulable openings, such as are indicated at G, (where a sliding shutter is shown for this purpose,) whereby any desired amount of draft can be admitted to the chamber.

B is a grating or grated platform upon which the article to be treated with the sand-blast is to be placed, andbelow the grating B is situated a hopper D, adapted to receive the sand and dirt resulting from the operation of the sand-blast upon the article under treatment, G being a conduit leading from the bottom of the hopper D, through which the sand is permitted to run, a damper g regulating its freedom of motion.

E and F are dust and air collecting pipes situated in the hopper and connected directly orindirectly with some air-sucking apparatus. It is through these pipes, which for certain purposes may be consolidated into a single pipe, that the air is drawn from the hopper and through the grating from the chamber A, a constant and energetic downdraft being thus secured through the grating and obviously through the chamber A also.

II and I are parts of a pneumatic elevator, as shown. II is a vessel divided into two chambers II and II by means of a partition H the uptake-pipe I leading through the chamber H and through the partition II into the chamber H Slots or perforations 72. are also formed through the partition I1 and below them an annular ring H is situated in the chamber H said plate being of such size as to leave an annular opening around its outer edge as well as the circular opening in its center, which should register substantially with the lower end of the uptake-pipe I. The pipe G, leading from the bottom of the hopper D, leads into the chamber II" and, as shown and as I prefer to construct it, a dustcollecting pipe, as F, situated in the hopperD, connects, as by conduit F, with the chamber II of the pneumatic elevator, f indicating a damper in pipe F It Will be seen that the sand, &c., passing through pipe G into the chamber II will issue through the opening 7L" into the chamber H, but the sand will run out of the opening h onto the annular plate H and in case the apparatus is not in operation will soon form little conical heaps upon the plate I1 which will seal the opening it and prevent the chamber H from filling up with sand.

When in operation, a blast of air enters the chamber II preferably, as shown, through the pipe F and this air-blast passing through the center opening in the plate H, as well as through the annular space indicated at h around the outer edges of the Plate H will sweep the sand into the opening in the uptakepipe I and upward through said uptake-pipe, the upper end of which I enters a sand-separating device, preferably a settling-chamber, such as indicated at J. This settling-chamher is Virtually a considerable enlargement of the uptake-pipe,in which the velocity of the air and sand is checked, so that the heavier particles will fall by gravity into the hopper shaped bottom J of the separator, and I have found it advantageous to construct this device, as shown, with a baffle-plate J situated between the top of the pipe I and the outtakepipc K,leadingfrom the separator,as by means of this baffle-plate the separator not only insures the checking of the velocity of the aircurrent, but also necessitates a change in its direction, which of course will facilitate the separation of the heavier particles of sand, and not only so, but avoids the sand-blast-like action which would take place if the sand was permitted, on issuing from the pipe I, to strike freely on the top of the separator.

J indicates a spout leading from the lower part of the hopper-bottom of the separator J, by which the sand can be withdrawn from time to t-ime,j indicating a valve in this pipe.

K is a pipe leading from the top of the sep* arator J, as shown, to a centrifugal separator L, having ahopper-shaped bottom L, the pipe K opening first into an enlarged, preferably cone-shaped conduit L situated in the shell of the separator L, and having in its upper part a screw-like deflector L by which the air coming from the pipe L is given a rapid rotary movement. The lower part of the conduit L is formed with a number of openings L, leading from it into the shell of the separat or and through which the heavier particles carried by the air are forced out to the space within the shell. The air itself, carrying of course a certain amount of dust, passes downward through the pipe M into the watertank N, which is a closed chamber partially filled with water to a level indicated at N, and the pipe M, preferably increasing in diameter, as indicated at M, passes through below the waterlevel in the tank, so that the air is forced to bubble up through the water and is thereby washed.

A grating, as indicated at M may be used to insure the breaking up of the air as it issues from the pipe-extension M. As shown, the dust-pipe E connects through a pipe E having a damper c with the enlarged portion 3 of the pipe M, and the air-space of the watertank N is connected through a conduit 0, leading from an opening N to a suction-blower,

as indicated at P.

To prevent the entry of large particles of sand into the dust-pipes E or F, I form these pipes with openings E and F, leading through their walls at the bottom, and provide them with deflecting-plates E E F F (best shown in Fig. 3,) so that only such thin stuff as would be carried upward in the hopper can enter the dustspipes with the air-currents.

Q indicates an air-compressor connecting through pipe R with a reservoir for compresed air, as indicated at 8, said reservoir connecting by a pipe T with the air-space U of a sand-blast apparatus U, 1, indicating a valve for regulating the admission of air to the sandblast apparatus and T indicating a press uregage. The sand-blast apparatusU, as shown. comprises the air-chamber U, a sand-chamber U connecting by a vertical passage U". having a regnlating-valve u with ahorizon tar air-passage U", opening freely into the airchamber U, the sand and air passing from air-passage U through flexible pipes V to the nozzles V.

As shown, the sand-blast apparatus is provided with hoppers U and U, U being t valve by which theopening in the hopper if can be closed, this valve being attached :0 the valve-rod U having the handle U U is the sand-valve of the hopper U an d is attached to a sliding valve-stem U having the handle U U indicating a spider resting on the hopperU and adapted to engage the handle U and prevent the valve U from opening beyond a determined distance.

This same function is performed for the valve U by the head or handle U upon, which the head or handle U rests when the valve U is open.

I have shown this sand-blast apparatus as so placed that-the pipe or pipes J", leading from the separator J, will conduct the sand into the upper hopperU from which, by opening the Valve U it will pass into the hopper U from which in turn, by opening the valve U it will pass into the sand-chamber U The operation of the device as a whole will be readily followed. The suction apparatus has the double function of elevating the sand coming from the hopper D and of maintaining an energetic and sufficient suction in the hopper D to insure that all dust will be drawn down through the grating, and as this latter function is apt to require greater energy than is required for the elevation of the sand I prefer to use the two dust-pipes E and F, one connecting with the elevator and the other connecting with the air-sucking apparatus without communication with the elevator, the dampers e and f permitting the nice regulation of the amount of air passing to the elevator and depended upon for the transportation of the sand. It is obviously possible to provide for the elevation of the sand coming from the hopper D by an air-current entirely distinct from that drawn from the hopper. though it is just as obvious that it is decidedly advantageous to use at least a portion of the air drawn from the hopper for the elevation of the sand also drawn from the hopper. The air and sand elevated by means of the pneumatic elevator II and I passing then to the separator J, the heavier and reusable portions of the sand are there separated from the air and lighter and unusable particles of sand and dust, which pass from the separator J to the centrifugal separator L, where a large portion of the fine sand is tossed, is separated from the air, and the air carrying only the very fine dust is then passed down into the water-tank N, where it is thoroughly washed and from which the air issues practically clean.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an apparatus for sand-blasting the combination of a grating as B adapted to support the article to be treated, a hopper for sand below said grating, one or more clustpipes as E, F, opening into said hopper and connected to an air-su cking apparatus, a conduit as G leading from the bottom of the hopper a pneumatic sand-elevator as H, 1, arranged to receive sand from conduit G, and a sand-separator as J, arranged to remove the sand and air from the elevator and separate the heavy from the light particles.

2. In an apparatus for sand-blasting the combination of a grating as B adapted to support the article to be treated, a hopper for sand below said grating, a dust-pipe as F opening into the hopper, a conduit G leading from the bottom of the hopper, a pneumatic sandelevator H, I, having a sand-chamber H into which conduit G leads and an air-chamber II connected as by pipe F with dust-pipe F, a sand-separator J arranged to receive the sand and air from the elevator and an airsuction apparatus arranged to draw air from the separator and through it from the hopper and elevator.

3. In an apparatus for sand-blasting the combination of a grating as B adapted to sup port the article to be treated, a hopper for sand below said grating, a dust-pipe as F opening into the hopper, a conduit G leading from the bottom of the hopper, a pneumatic sand-elevator II, I, having a san d-chamber II into which conduit G leads and an air-cha1nber II" connected as by pipe F with dust-pipe I a sandseparator J arranged to receive the sand and air from the elevator, a water-tank N, a conduit as K Ill. leading from the separater to said tank and below the water-level thereof, and an air-suction apparatus con- 45 nected with said tank above its water-level.

4. In an apparatus for sandblasting the combination of a grating as B adapted to support the article to be treated, a hopper for sand below said grating, a dust-pipe as F opening into the hopper, a conduit G leading from the bottom of the hopper, a pneumatic sand-elevator H, I, having a sand-chamber H into which conduit G leads and an air-chamber I-I" connected as by pipe F with dust-pipe F, a sand-separator J arranged to receive the sand and air from the elevator, a water-tank N, a conduit as K, M leading from the separator to said tank and below the water-level thereof, a dust-pipe as E opening like pipe F into the hopper D, a conduit as E connecting dust-pipe E with conduit M, dampers as f and e situated in pipes F and E and an airsuction apparatus connected with tank N above the water-level.

5. In an apparatus for sand-blasting the combination of a grating as B adapted to support the article to be treated, a hopper for sand below said grating, a dust-pipe as F opening into the hopper, a conduit G leading from the bottom of the hopper, a pneumatic sand-elevator H, I, having a sand-chamber I-I into which conduit G leads and an air-chamber H connected as by pipe F with dust-pipe F, a sand-separator J arranged to receive the sand and air from the elevator, a conduit K leading from the settling-chamber, a centrifugal separator L arranged to separate sand coming from conduit K, a water-tank N, a conduit M leading from separator L below the water-level of tank N and an air-suction apparatus connected with the air-space of the tank.

13. G. TILGIIMAN, JR.

Vitnesses ROBERT W. LLorn, D. STEWART. 

